Coral Reef Ecosystems
The ocean is a large body of salt water that covers more than 70 percent of the Earth’s surface and gives the Earth its deep blue color.
Within the ocean are a range of different ecosystems. The average depth of the ocean is over 3.5 kilometers. Most organisms can be found at depths of less than 100 meters. At this depth, sunlight can reach plants like seagrasses so they can photosynthesize.
Coral reefs are the most biodiverse ecosystems in the ocean. They are composed of colonies of small stationary animals called corals. There are two main types of corals: hard corals that build reefs by secreting calcium carbonate, and soft corals, like sea anemones and sea fans, that sway with the currents.
Reefs provide a protective haven for a vast array of marine life. Among the vertebrates, sea turtles and sea snakes glide through the coral structures while a colorful array of fish dart around. From tiny clownfish hiding in anemones to formidable reef sharks, rays, and eels, the diversity of fish is stunning.
Coral reefs are also home to an impressive variety of invertebrates. Crustaceans such as lobsters and crabs scuttle across the ocean floor, while clams and other mollusks nestle within the coral structures. Jellyfish, squid and octopus are also common coral reef invertebrates.
Related Printables.
Our Local Ecosystems
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Ecosystems and Habitats
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Wetland Ecosystems
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Tropical Rainforest Ecosystems
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Temperate Forest Ecosystems
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Coral Reef Ecosystems
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Producers, Consumers and Decomposers
![](https://ngscience.com/wp-content/uploads/4-NGScience-Ecosystems_07.small_.jpg)
Types of Consumers
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Energy in Ecosystems – Comprehension
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Food Chains
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Food Webs
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Review – Ecosystems
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